AktiraAktira JEE
Subscribe
PhysicsJEE Main 21 Jan 2026, Shift 2·Q13·MCQ·Easy–moderate

Mechanical Properties of Fluids · Surface tension

Surface tension of two liquids (having same densities), T1T_1 and T2T_2, are measured using capillary rise method utilizing two tubes with inner radii of r1r_1 and r2r_2 where r1>r2r_1 > r_2. The measured liquid heights in these tubes are h1h_1 and h2h_2 respectively. [Ignore the weight of the liquid above the lowest point of meniscus]. The heights h1h_1 and h2h_2 and surface tensions T1T_1 and T2T_2 satisfy the relation :
  1. (1)h1<h2h_1 < h_2 and T1=T2T_1 = T_2
  2. (2)h1=h2h_1 = h_2 and T1=T2T_1 = T_2
  3. (3)h1>h2h_1 > h_2 and T1=T2T_1 = T_2
  4. (4)h1>h2h_1 > h_2 and T1<T2T_1 < T_2
We corrected a printing error in the original paper

Source printed “about the lowest point of miniscus”.

Video solution coming soon

We're animating every PYQ step by step. Subscribe to get them first.

Subscribe

See the full 21 Jan 2026, Shift 2 paper

More on Surface tension